CBC: Researchers report answer to global shortage of N95 masks amid COVID-19 crisis
A group of Manitoba researchers say they’ve found a way to safely decontaminate and reuse some types of medical masks that are normally thrown away after each use.
The COVID-19 pandemic has caused global shortages of personal protective equipment for health-care workers around the world, including N95 respirators and masks.
A team of five Manitoba researchers released a study Wednesday which tested decontamination of four types of masks, finding some success.
Led by Dr. Anand Kumar, a professor of medicine at the University of Manitoba, he said preliminary results suggest some masks could be successfully decontaminated and reused up to 10 times, using common sterilization techniques.
“It became apparent in the early course of the epidemic that we were going to burn through personal protective equipment quite rapidly,” said Kumar, who also works as a critical care physician at Health Sciences Centre and has a background in infectious diseases….
In the early stages of the pandemic, shortages of N95 masks and other personal protective gear were being reported, Kumar said.
“Physicians and other health-care workers were having to use their masks and other equipment for days on end which is specifically recommended against,” he said….
Two of the methods, Kumar said, successfully allowed for multiple cleanings with no loss of function in terms of their filtering ability.
One of those methods, using vaporized hydrogen peroxide, was very effective in decontaminating all types of masks while preserving their effectiveness, Kumar said.
However, he added the technology is only available in a few places in North America.
A more common method, autoclaving, which is found in nearly every hospital setting, was also very effective, he said.
“[Autoclaving] is like a pressure cooker, basically you enclose items into a chamber, you lock down the chamber, you heat it up and actually increase the pressure inside the chamber and basically it becomes a pressure cooker,” Kumar said.
The machines heat up to about 121 C for 15 minutes, killing bacteria and viruses.
“It’ll sterilize anything.”
“Now the assumption has been that if you tried this on an N95 mask they would degrade rapidly. We thought we’d give it a try anyway,” Kumar said.
“And actually what we found is while it does degrade some masks there’s a certain group of masks that are made kind of a fabric type material, rather than being moulded closely to the face… they’re called pleated [masks],” he said….